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The HiPowAR project deals with the development, design, and manufacture of a device for the direct conversion of renewable ammonia into electricity. One of the basic technological principles of the project are ceramic membranes, whose specific property is the exclusive permeability of oxygen (ambient air is supplied to one side of the membrane and only oxygen passes through the membrane)
HiPowAR

For additional details visit the official project website: http://www.hipowar.eu
The project is implemented with the support of the EU Horizon 2020 research and innovation program.

Introduction of the HiPowAR project

The complex and long-term energy transformation process requires continuous research and exploration toward innovative technological solutions to mitigate the impact of climate change and find efficient and affordable energy sources that are sustainable in the long term with regard to competitiveness, reliability, and high quality of energy supply to end consumers. These goals are in line with the central motive of the HiPowAR research and development project. PBS Brno, within the consortium of 6 European partners responsible for the project implementation, collaborates on developing a membrane reactor that will enable the efficient use of ammonia (NH3), considered a carbon-free and synthetically producible fuel for stationary electricity sources and vehicle propulsion.
In terms of efficiency, membrane reactor technology is comparable to solid oxide fuel cells (SOFC) technology, but it is not as complex, which has a positive effect on lower production costs. Like fuel cells, a membrane reactor converts chemical energy into electrical energy, making it more efficient than fuel combustion systems. Additional advantages are the minimal amount of emitted pollutants, compact size, and quiet operation. The practical significance of the membrane reactor's technical solution lies in the efficient utilization of ammonia as the sole fuel, so it is not a hybrid system using any conventional fuels.

Renewable ammonia as an energy source

The efficient use of ammonia in the HiPowAR system represents an essential requirement for being classified as a fully renewable, long-term sustainable and efficient energy-production system. Renewable ammonia is a carbon-free synthetic fuel considered one of the possible pathways to a nitrogen-based energy economy. Unlike synthetic hydrocarbon-based fuels, ammonia has the advantage of producing no CO2 emissions and has an energy density almost double that of hydrogen. In the context of alternative fuel use to reduce fossil fuel consumption, ammonia constitutes a critical link in the energy transformation process and transition to hydrogen technologies and their supplementation. This is mainly because of an already existing extensive infrastructure for the synthetic production of ammonia and its transport which, in the case of ammonia, is easier to develop compared to hydrogen, especially in countries affected by energy poverty.
Ammonia is the second most used inorganic chemical worldwide, with an estimated consumption of 180 million tonnes per year, mainly due to its use for fertilizer production. Until recently, ammonia was primarily associated with this use, but technological developments in fuel cell systems for transport (so far largely for marine operations) and energy production made ammonia become an appealing hydrogen carrier for modern fuel cell engines, industrial boilers, and reactors with 100% zero carbon footprint. It is also currently estimated that hydrogen production and storage is approximately ten times more expensive than that of ammonia due to the need to store hydrogen at cryogenic temperatures. From a historical perspective, the experimental use of both substances as fuels for internal combustion engines dates back to the early 19th century. A century later, interest in hydrogen and ammonia was renewed due to industrial development and, in the case of ammonia, also due to insufficient oil reserves during World War II, making it a substitute for gasoline for public transportation.
Although synthesis technologies for ammonia production, which are the subject of other research and development projects, can further increase the competitiveness of ammonia as a sustainable energy source, the development of the HiPowAR membrane reactor is a significant initiative for the efficient commercial use of an available, clean, renewable, and established fuel – ammonia.

The technical solution of a membrane reactor

The HiPowAR project deals with the development, design, and manufacture of a device for the direct conversion of renewable ammonia into electricity. One of the basic technological principles of the project are ceramic membranes, whose specific property is the exclusive permeability of oxygen (ambient air is supplied to one side of the membrane and only oxygen passes through the membrane). A certain quantity (for our research device in the order of hundreds, more in future applications) of such membranes in the form of narrow tubes is placed in an insulated pressure vessel – membrane reactor. Oxygen (through the membranes), ammonia (which serves as fuel) and water (membrane reactor coolant) are fed to the membrane reactor. Ammonia and oxygen initiate a chemical reaction, the so-called pressurized flameless combustion producing heat, water vapour and nitrogen. The operational parameters inside the reactor depend on the amount of cooling water supply, but the current project phase aims at 50 bar(a) and 900°C.
The mixture of water vapour and nitrogen created in this process is then injection-cooled or throttled as required to achieve optimal parameters and fed to the expander. The mixture of media is expanded in the expander which results in electricity generation. Subsequently, the mixture is fed to a condenser, where the gaseous mixture is reduced to liquid and nitrogen is separated from the mixture. The condensed water is largely reused in the membrane reactor cooling system and to a lesser extent drained from the system for further use. Following the principle of chemical reaction, no water is necessary to be added water to this system, as is the case with most energy-producing devices, instead this system produces excess water.

Objectives of the HiPowAR project

Within the framework of the HiPowAR project, the task of PBS Brno is the design and construction of a test rig for testing properties of various types of O2 permeable membranes within the membrane reactor. This test rig will also allow for electricity generation from the heat produced in the membrane reactor. For this purpose, PBS Brno will design and supply an expander. Also, the expander will be replaceable in the test rig system by other devices with the same purpose. Some of these devices will also be supplied by partners within the consortium. For example, Ranotor will provide its steam engine. In addition to the fundamental parts of the entire system – membrane reactor and expander – PBS Brno will also design and provide all other parts of the system, namely connecting pipes, pumps, fittings and more.

Research and development of new O2 permeable membranes and their subsequent testing – one type of membrane has been already tested and is ready for use, but the project aims to develop and test more types. This goal is not within the scope of work of PBS Brno.
O2 permeable membranes test equipment design and manufacturing – complete design and production of all necessary parts for the test rig system, which will use the above-described principle of electricity production from ammonia using O2 permeable membranes. The test equipment also includes the design and manufacture of an expander for the test rig. This assignment is entirely within the scope of work of PBS Brno.
Research of pressurized flameless ammonia combustion – another goal of the project is to investigate and characterize the process of pressurized flameless ammonia combustion, as it is not a conventional and thoroughly researched principle. This task is partly within the scope of PBS Brno, which will participate in experimental testing.

Assessment of future practical use with higher-powered devices – the size of the test rig will be approximately 10 kWe. Further project goals deal with modelling and device scalability analysis for possible future use in a larger system and at a higher performance level. The commercial viability and operation of a large-scale membrane reactor will also be assessed from an economic and environmental perspective. This goal is not within the scope of PBS Brno.
 
The project is implemented with the support of the EU Horizon 2020 research and innovation program.
For additional details visit the official project website:

http://www.hipowar.eu